Electrical distribution systems, for example in a building or industrial facility, typically supply electricity to non-linear loads, such as adjustable speed motor drives, uninterruptible power supplies (UPS), battery chargers, servo drives, and welders. These loads produce various levels of current at harmonic frequencies in the power distribution system with the harmonic spectrum depending upon the nature of the load. Typically, variable frequency drives can experience substantial harmonic distortion caused by non-linear loads. Typically, magnitude of harmonic currents in an individual non-linear load depends on the total effective input reactance, which can be a product of a source reactance plus added line reactance.